Follow up bugs from the initial review comments

[Gary Adams]

I deferred a number of changes in order to get the first set of sources 
out to the mobile/dev repos.
Just so we don't lose sight of those changes, I've filed a few bugs that 
can be addressed independently
going forward.

  JDK-8145802: CPPFLAGS sysroot support
  JDK-8145804: ARFLAGS versus AR_OUT_OPTION conflicts in static builds
  JDK-8145806: OPENJDK_TARGET_CPU_LEGACY_LIB build variable will be retired
  JDK-8145807: JavaLauncher should use standard naming and build constructs
  JDK-8145809: Demo projects for HelloWorld for ios and android
  JDK-8145811: Fix compiler warnings